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                                                                     EXHIBIT 4.2

                AMENDMENT NO. 6 TO CREDIT AND SECURITY AGREEMENT

      This Amendment No. 6 to Credit and Security Agreement ("Agreement No. 6")
dated effective as of the 23rd day of April, 2004, by and between COHESANT
TECHNOLOGIES INC., a Delaware corporation (hereinafter referred to as
"Borrower"), and UNION PLANTERS BANK, N.A., a national banking association
(hereinafter referred to as "Bank").

                                   WITNESSETH:

      WHEREAS, the Borrower and the Bank are parties to that certain Credit and
Security Agreement dated as of the 15th day of May, 1998, as amended by that
certain Amendment No. 1 to Credit and Security Agreement dated April 13, 1999,
as further amended by that certain Amendment No. 2 to Credit and Security
Agreement dated April 17, 2000, as further amended by that certain Amendment No.
3 to Credit and Security Agreement dated April 1, 2001, as further amended by
that certain Amendment No. 4 to Credit and Security Agreement dated April 29,
2002, and as further amended by that certain Amendment No. 5 to Credit and
Security Agreement dated March 25, 2003 (hereinafter referred to as
"Agreement"); and

      WHEREAS, the Borrower desires to renew the financial accommodations
previously extended by the Bank; and

      WHEREAS, the Bank is willing to provide such financial accommodations to
the Borrower on the terms and subject to the conditions in the Agreement as
amended by the terms and conditions of this Amendment No. 6.

      NOW, THEREFORE, in consideration of the premises, the mutual covenants
hereinafter contained, and other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the parties agree as follows:

      Section 1. Effect of this Amendment No. 6. This Amendment No. 6 shall not
change, modify, amend or revise the terms, conditions and provisions of the
Agreement, the terms and provisions of which are incorporated herein by
reference, except as expressly provided herein and agreed upon by the parties
hereto. This Amendment No. 6 is not intended to be nor shall it constitute a
novation or accord and satisfaction of the outstanding instruments by and
between the parties hereto. Borrower and Bank agree that, except as expressly
provided herein, all terms and conditions of the Agreement shall remain and
continue in full force and effect. The Borrower acknowledges and agrees that the
indebtedness under the Agreement remains outstanding and is not extinguished,
paid, or retired by this Amendment No. 6, or any other agreements between the
parties hereto prior to the date hereof, and that Borrower is and continues to
be fully liable for all obligations to the Bank contemplated by or arising out
of the Agreement. Except as expressly provided otherwise by this Amendment No.
6, the credit facilities contemplated by this Amendment No. 6 shall be made
according to and pursuant to all conditions, covenants, representations and
warranties contained in the Agreement.

      Section 2. Definitions. Terms defined in the Agreement which are used
herein shall have the same meaning as set forth in the Agreement unless
otherwise specified herein.

      Section 3. Amendment of Agreement. Subject to the satisfaction of the
conditions precedent set forth in Section 5 herein, the Agreement is amended as
follows:

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      The first sentence of Subsection 2.1.1 of the Agreement is hereby amended
and replaced with the following:

      2.1.1 The obligation of the Borrower to repay the Line of Credit Loans
      shall be evidenced by the Line of Credit Note which shall be repayable on
      or before May 1, 2005 ("Maturity").

      Section 4. Conditions Precedent. This Amendment No. 6 shall become and be
      deemed effective in accordance with its terms immediately upon the Bank
      receiving:

            a)    Two (2) copies of this Amendment No. 6 duly executed by the
      authorized officers of the Borrower and the Bank.

            b)    One (1) copy of the Line of Credit Note reflecting the revised
      Maturity duly executed by an authorized officer of the Borrower.

            c)    Two (2) copies of a Consent and Confirmation of Guaranty
      executed by each of the Guarantors.

            d)    Certificates of Existence regarding Borrower and Guarantors
      issued by the appropriate Secretary of the State's Office.

            e)    Such other documents and items as the Bank may reasonably
      request.

      Section 5. Representations and Warranties of the Borrower. The Borrower
      hereby represents and warrants, in addition to any other representations
      and warranties contained herein, in the Agreement, the Loan Documents (as
      defined in the Agreement) or any other document, writing or statement
      delivered or mailed to the Bank or its agent by the Borrower, as follows:

            a)    This Amendment No. 6 constitutes a legal, valid and binding
      obligation of the Borrower enforceable in accordance with its terms. The
      Borrower has taken all necessary and appropriate corporate action for the
      approval of this Amendment No. 6 and the authorization of the execution,
      delivery and performance thereof.

            b)    As of the date hereof, there is no Event of Default or Default
      under the Agreement, the Amendment No. 6 or the Loan Documents.

            c)    The Borrower hereby specifically confirms and ratifies its
      obligations, waivers and consents under each of the Loan Documents.

            d)    Except as specifically amended herein, all representations,
      warranties and other assertions of fact contained in the Agreement and the
      Loan Documents continue to be true, accurate and complete.

            e)    There have been no changes to the Articles of Incorporation,
      By-Laws, or the compositions of the Board of Directors of the Borrower
      since execution of the Agreement.

            f)    Borrower acknowledges that the definition "Loan Documents"
      shall include this Amendment No. 6 and all the documents executed
      contemporaneously herewith.

      Section 6. Affirmative Covenants. By entering into this Amendment No. 6,
      Borrower further specifically undertakes to comply with the obligations,
      terms and covenants as contained in the Agreement and agrees to comply
      therewith as such relate to the credit facilities and accommodations as
      provided to the Borrower pursuant to the terms of this Amendment No. 6.

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      Section 7. Governing Law. This Amendment No. 6 has been executed and
      delivered and is intended to be performed in the State of Indiana and
      shall be governed, construed and enforced in all respects in accordance
      with the substantive laws of the State of Indiana.

      Section 8. Headings. The section headings used in this Amendment No. 6 are
      for convenience only and shall not be read or construed as limiting the
      substance or generality of this Amendment No. 6.

      Section 9. Survival. All representations, warranties, and covenants of the
      Borrower herein or any certificate, agreement or other instrument
      delivered by or on its behalf under this Amendment No. 6 shall be
      considered to have been relied upon by the Bank and shall survive the
      making of the Loans and delivery to the Bank of the Line of Credit Note.
      All statements and any such certificate or other instrument shall
      constitute warranties and representations hereunder by the Borrower, as
      the case may be.

      Section 10. Counterparts. This Amendment No. 6 may be signed in one or
      more counterparts, each of which shall be considered an original, with the
      same effect as if the signatures were upon the same instrument.

      Section 11. Modification. This Amendment No. 6 may be amended, modified,
      renewed or extended only by written instrument executed in the manner of
      its original execution.

      Section 12. Waiver of Certain Rights. The Borrower waives acceptance or
      notice of acceptance hereof and agrees that the Agreement, this Amendment
      No. 6, the Line of Credit Note, and all of the other Loan Documents shall
      be fully valid, binding, effective and enforceable as of the date hereof,
      even though this Amendment No. 6 and any one or more of the other Loan
      Documents which require the signature of the Bank, may be executed by and
      on behalf of the Bank on other than the date hereof.

      Section 13. Waiver of Defenses and Claims. In consideration of the
      financial accommodations provided to the Borrower by the Bank as
      contemplated by this Amendment No. 6, Borrower hereby waives, releases and
      forever discharges the Bank from and against any and all rights, claims or
      causes of action against the Bank arising under the Bank's actions or
      inactions with respect to the Loan Documents or any security interest,
      lien or collateral in connection therewith as well as any and all rights
      of set off, defenses, claims, causes of action and any other bar to the
      enforcement of the Loan Documents which exist as of the date hereof.

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      IN WITNESS WHEREOF, COHESANT TECHNOLOGIES, INC. and UNION PLANTERS BANK,
N.A. have caused this Amendment No. 6 to Credit and Security Agreement to be
executed by their respective duly authorized officers effective as of the 23rd
day of April, 2004.

                                                 COHESANT TECHNOLOGIES INC.

                                                 ("Borrower")

                                                 By:____________________________

                                                 Printed:_______________________

                                                 Title:_________________________

                                                 UNION PLANTERS BANK, N.A.

                                                 ("Bank")

                                                 By:____________________________

                                                 Printed:_______________________

                                                 Title:_________________________

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